Myeloid cells, such as dendritic cells and macrophages, can instruct the adaptive immune system to mount a response against tumor cells and pathogens by presenting peptide antigens to T cells while expressing immunogenic cytokines and costimulatory signals, thereby promoting cytotoxic T cell activation and proliferation. Conversely, in a steady state condition, myeloid cells maintain tolerance to endogenous proteins by presenting self-antigens to T cells in the context of non-immunogenic signals, such as regulatory cytokines, which can promote regulatory T cells and suppress immunogenicity.
Cancer cells can evade the immune system by engaging signaling pathways associated with immunosuppressive or immunoregulatory antigen presentation. Such evasion events represent a major obstacle to therapeutic strategies that rely on promoting anti-tumor immunity. Therefore, there is a need for therapeutic compositions and methods that prevent tumor-induced immunosuppression and promote immunogenic presentation of tumor antigens by myeloid cells.